Contribution to strategic maintenance and renewal of public infrastructure(8) Research on the maintenance and reconstruction of the infrastructure
subject to frost damage and combined effect of deterioration
Research Period: FY2016-2021
Program leader: Director of Cold-Region Maintenance Engineering Research Group

Research Summary

Soundness of infrastructure is severely deteriorated
under cold and snowy environment due to combined
effect of deterioration mainly of frost damage
Bridge(bridge slab pavement/Bridge slab)

Frost damage/salt damage

Frost damage/salt damage/fatigue(substructure/wheel guard, etc.)

Coastal structures

Pavement

Frost damage/wear caused by sea ice

Freeze-thaw, snowmelt water(groundsill, etc.)

Frost damage/wear

R&D Program

River structures

Heave cut slop

(drain ditch on berm, etc.)

Frost heave

Countermeasures for frost damage/ deterioration by
combined effect are undeveloped(1) Establish efﬁcient methods forinspection, diagnose and evaluation

Experimental study bywheel running machine(2) Establishment of reliable technology
for repair and reinforcement

Measurement ofdeﬂection due to fallingweightExample of soundness evaluation of bridge slabs
suffering fatigue, frost damage and salt damage

BeforeAfter

Example of repair of concrete sheet pile seawall thathas suffered the frost damage and wear(3) Establishment of technologies for reconstruction
and new construction with higher durability

Drainage materialusing new material

Field test construction situation

Example of countermeasures for the frost heave ofdrain ditch on berm in cut slope(4) Systematization of inspection, diagnosis, assessment, repair/reinforcement, reconstruction/new construction related to the infrastructures due to frost and combined effect of deterioration.
Compile as "Countermeasure manual of deterioration by combined effect with frost damage(draft)”

Propose application in standards and disseminate research
results through technical guidance
Prolonging the service life of infrastructures in the snowy and cold regions and ensure saety/security
For the aging of public infrastructure, we need to understand theconditions of deterioration according to various effects such asenvironmental conditions and make a plan of maintenance andrenewal based on the importance of facilities. We also need toestablish a series of systematic engineering. Particularly for the publicinfrastructure in the snowy and cold regions, frost damages anddeterioration by combined effect such as low temperature, snow,frost, frost heave, freeze-thaw, snowmelt water, salt occur due to harshenvironments. However, countermeasures for these deterioration
caused by combined effect has not fully developed yet.
For bridges, rivers and coast of concrete structures, paving, heave cut
slope, in this research we develop structure-specific technology andcommon technology targeted at frost damage and its deterioration by
combined effect/damage mechanism with related to the following 4
items;(1)	Establishment of efficient inspection, diagnosis and evaluation
methods of frost damage/deterioration by combined effect(2)	Establishment of a reliable repair/reinforcement technology for
frost damage/deterioration by combined effect(3)	Establishment of technology of durable reconstruction and new
construction for frost damage/deterioration by combined effect(4)	Systematization of inspection, diagnosis, assessment, repair/reinforcement, reconstruction/new construction related toinfrastructures due to frost damage/deterioration by combinedeffect.
We support to help maximize and extend the life of infrastructures inthe snowy and cold environment by applying these technologies tothe infrastructure, which will contribute to maintenance, development
and utilization of the land structure to support the safety and security
and economic growth.
PUBLIC WORKS RESEARCH INSTITUTE 201613